Civil aviation accidents in the UK are investigated by the Air Accident Investigation Branch (AAIB), part of the Department for Transport. There are many factors that can lead to an aviation accident, one of which is weather conditions that can affect an aircraft or airport.
In accordance with International, European, and National requirements the Met Office is required to produce an Aftercast report if asked to by the AAIB. An Aftercast differs from a forecast in the sense that it is a report of historical conditions leading up to and at the time of the accident. The Aftercast provides synoptic charts, satellite imagery, the Terminal Aerodrome Forecasts (TAFs) if relevant, and a spot wind analysis. Reports can even include Aircraft Meteorological Data Relay (AMDAR) information, which is real time weather data collected by nearby aircraft in flight. All of the information is analysed in further detail and a summary of the most probable weather conditions that existed at the time of the incident is provided.
The meteorologist compiling the Aftercast gives no opinion in relation to the accident and the report is without speculation on the part of the Met Office.
So what do the AAIB do with the information provided? It is the job of its inspectors to combine the met data with the other evidence they have to reach a possible conclusion as to the cause of the accident and whether or not the meteorological conditions influenced the accident. Aviation accident investigations are a process of elimination, so even if the weather played no part in the incident the report is still valuable, as it allows investigators to discount the meteorological situation and focus on other factors.
Weather can be a crucial element in the ‘perfect storm’ of conditions required to result in an accident, be it the decisions the pilot takes in response to it or how the aircraft’s critical systems are designed to mitigate its effects.
The AAIB’s role is not only to determine the cause of an accident but also to make recommendations for change to avoid a repetition of the same problem. Weather will continue to impact aviation and the Met Office’s contribution to accident reports will remain an important one.
Jonny Hughes- Account Manager